Airfoil with a landing flap having a flexible trailing edge

Abstract

A lifting airfoil (10) includes a landing flap (20) movably connected to a main airfoil body (10') so as to form at least a portion of the trailing edge of the airfoil. The landing flap (20) includes a leading edge nose (21) and a trailing edge body (22), which are each bounded by an upper cover skin (23) and a lower cover skin (24). The trailing edge body (22) is connected to the leading edge (21) by the continuous upper cover skin (23), while a gap (25) interrupts the lower cover skin (24) between the leading edge nose (21) and the trailing edge body (22). The flap (20) is mounted on a carriage (31) that moves along a guide rail (30) so as to be slidably and pivotably extendable during take-off and landing phases of a flight. Furthermore, the trailing edge body (22) is elastically flexible and can be deflected as needed for adjusting the camber thereof during cruise flight by operating an actuating device (29) that is pivotably connected between a trailing edge area of the trailing edge body (22) and the guide rail (30).

What is claimed is: 
     
       1. A lifting airfoil comprising: an airfoil body having a forward edge and a rear edge,   a flap movably connected to said airfoil body at said rear edge, wherein said flap comprises a flap leading edge nose and a flap trailing edge body, said flap trailing edge body is elastically flexible, said flap trailing edge body terminates along a flap trailing edge that forms a trailing edge of said airfoil, and said flap leading edge nose and said flap trailing edge body comprise and are bounded by a pressure-side cover skin and a vacuum-side cover skin, and   an actuating device that is arranged externally of said flap, pivotally connected to said flap, and adapted to selectively elastically bend said flap trailing edge body.   
     
     
       2. The lifting airfoil according to claim 1, wherein said flap leading edge nose is flexurally stiff and unbendable relative to said flap trailing edge body. 
     
     
       3. The lifting airfoil according to claim 1, wherein said flap trailing edge body further comprises transverse webs extending in a span width direction of said airfoil, and said transverse webs respectively interconnect and support said pressure-side cover skin and said vacuum-side cover skin. 
     
     
       4. The lifting airfoil according to claim 3, wherein said flap trailing edge body excludes webs extending in a chord length direction of said airfoil. 
     
     
       5. The lifting airfoil according to claim 3, wherein said cover skins are rigidly secured to said transverse webs. 
     
     
       6. The lifting airfoil according to claim 3, wherein said cover skins are elastically flexible, and said transverse ribs are so arranged so that said flap trailing edge body is elastically flexibly bendable in a plane perpendicular to said transverse webs and is resistant to bending in a plane parallel to said transverse webs. 
     
     
       7. The lifting airfoil according to claim 1, wherein at least one of said cover skins has a thickness that is variable along a chord length direction of said airfoil. 
     
     
       8. The lifting airfoil according to claim 1, wherein said vacuum-side cover skin is relatively thicker at said flap leading edge nose and relatively thinner toward said flap trailing edge on said flap trailing edge body, and said pressure-side cover skin has a uniform thickness everywhere. 
     
     
       9. The lifting airfoil according to claim 1, wherein said flap leading edge nose and said flap trailing edge body are connected to each other by only one of said cover skins extending continuously over said nose and said body, and the other of said cover skins is interrupted by a gap between said nose and said body. 
     
     
       10. The lifting airfoil according to claim 9, wherein said vacuum-side cover skin is said one of said cover skins extending continuously over said nose and said body, and said pressure-side cover skin is said other cover skin interrupted by said gap. 
     
     
       11. The lifting airfoil according to claim 9, further comprising a locking member arranged to selectively lock together said nose and said body at said gap, and not including any other connection between said nose and said body. 
     
     
       12. The lifting airfoil according to claim 1, further comprising a moveable support arrangement arranged and connected to said flap trailing edge body between said actuating device and a junction of said flap trailing edge body and said flap leading edge nose, wherein said moveable support arrangement is so arranged and adapted to support said flap trailing edge body while moving along with movements of said flap. 
     
     
       13. The lifting airfoil according to claim 1, wherein at least one of said cover skins of said flap trailing edge body is tangentially displaceable to a limited extent relative to said flap leading edge nose. 
     
     
       14. The lifting airfoil according to claim 13, wherein a free movement gap exists between said flap leading edge nose and said flap trailing edge body so as to allow said at least one of said cover skins of said flap trailing edge body to be tangentially displaceable to a limited extent relative to said flap leading edge nose. 
     
     
       15. The lifting airfoil according to claim 13, further comprising means for selectively locking said tangential displaceability of said at least one cover skin. 
     
     
       16. A lifting airfoil comprising: an airfoil body having a forward edge and a rear edge,   a flap movably connected to said airfoil body at said rear edge, wherein said flap comprises a flap leading edge nose and a flap trailing edge body, said flap trailing edge body is elastically flexible, said flap trailing edge body terminates along a flap trailing edge that forms a trailing edge of said airfoil, and said flap leading edge nose and said flap trailing edge body comprise and are bounded by a pressure-side cover skin and a vacuum-side cover skin,   an actuating device that is pivotally connected to said flap and that is adapted to selectively elastically bend said flap trailing edge body, and   a movement mechanism whereby said flap is movably connected to said airfoil body and enabled to be extended away from said airfoil body, wherein said movement mechanism comprises a guide rail connected to said airfoil body and extending rearwardly therefrom, a carriage arranged to be movable along said guide rail, and a forward bearing bracket connecting said flap leading edge nose to said carriage.   
     
     
       17. The lifting airfoil according to claim 16, wherein said actuating device is pivotally connected to said flap trailing edge body and is further pivotally connected to said guide rail. 
     
     
       18. The lifting airfoil according to claim 16, further comprising a moveable support arrangement that is arranged and connected to said flap trailing edge body between said actuating device and a junction of said flap trailing edge body and said flap leading edge nose and that is further connected to said forward bearing bracket, wherein said moveable support arrangement is so arranged and adapted to support said flap trailing edge body while moving along with movements of said flap. 
     
     
       19. The lifting airfoil according to claim 16, wherein said flap leading edge nose is rigidly secured to said forward bearing bracket, and further comprising a first pivot bolt that has a bolt axis extending in a span width direction of said airfoil and that pivotally connects said forward bearing bracket with said carriage, such that said flap leading edge nose and said forward bearing bracket together are pivotable about said bolt axis relative to said carriage. 
     
     
       20. The lifting airfoil according to claim 19, further comprising a first locking bolt that selectively lockingly connects said forward bearing bracket with said carriage, such that the pivotability of said flap leading edge nose and said forward bearing bracket is selectively blockable by said first locking bolt. 
     
     
       21. The lifting airfoil according to claim 16, wherein said forward bearing bracket is rigidly secured to said carriage, and further comprising a second pivot bolt that has a bolt axis extending in a span width direction of said airfoil and that pivotally connects said flap leading edge nose with said forward bearing bracket, such that said flap leading edge nose is pivotable about said bolt axis relative to said forward bearing bracket and said carriage. 
     
     
       22. The lifting airfoil according to claim 21, further comprising a second locking bolt that selectively lockingly connects said flap leading edge nose with said forward bearing bracket, such that the pivotability of said flap leading edge nose is selectively blockable by said second locking bolt. 
     
     
       23. The lifting airfoil according to claim 1, wherein said flap is movably connected to said airfoil body in such a manner that said flap leading edge nose is pivotable relative to said airfoil body about a pivot axis extending in a span width direction of said airfoil. 
     
     
       24. The lifting airfoil according to claim 23, further comprising means for selectively blocking the pivoting of said flap leading edge nose about said pivot axis. 
     
     
       25. A lifting airfoil comprising: an airfoil body having a forward edge and a rear edge,   a flap movably connected to said airfoil body at said rear edge, wherein said flap comprises a flap leading edge nose and a flap trailing edge body, said flap trailing edge body is elastically flexible, said flap trailing edge body terminates along a flap trailing edge that forms a trailing edge of said airfoil, and said flap leading edge nose and said flap trailing edge body comprise and are bounded by a pressure-side cover skin and a vacuum-side cover skin, and   an actuating device that is pivotally connected to said flap and that is adapted to selectively elastically bend said flap trailing edge body,   wherein said flap is movably connected to said airfoil body in such a manner that said flap is slidably extendable away from said airfoil body, and said actuating device is arranged and adapted to interconnect said flap and said airfoil body so that said actuating device can tiltingly pivot and thereby cause said flap to pivot relative to said airfoil body as said flap is slidingly extended away from said airfoil body.   
     
     
       26. The lifting airfoil according to claim 1, further comprising a control unit that is connected for control signal transmission at least to said actuating device, and that is adapted to control and coordinate all movements of said flap relative to said airfoil body and of said flap trailing edge body relative to said flap leading edge nose. 
     
     
       27. The lifting airfoil according to claim 1, wherein said flap and said actuating device are so arranged and adapted to be able to achieve an elastic bending deflection of said flap trailing edge body selectively upward and downward from a neutral position in an angular range of at least ±15° about said neutral position, without a fixed distinct deflection axis about which said bending deflection occurs. 
     
     
       28. A method of varying the camber of a lifting airfoil including: an airfoil body having a forward edge and a rear edge,   a flap movably connected to said airfoil body at said rear edge, wherein said flap comprises a flap leading edge nose and a flap trailing edge body, said flap trailing edge body is elastically flexible, said flap trailing edge body terminates along a flap trailing edge that forms a trailing edge of said airfoil, and said flap leading edge nose and said flap trailing edge body comprise and are bounded by a pressure-side cover skin and a vacuum-side cover skin, and   an actuating device that is pivotally connected to said flap and that is adapted to selectively elastically bend said flap trailing edge body,   said method comprising the following steps: a) simultaneously pivoting said flap relative to said airfoil body and slidingly extending said flap away from said airfoil body during at least one of a take-off phase and a landing phase of a flight, and   b) operating said actuating device so as to elastically flexibly bend and deflect said flap trailing edge body away from a neutral position during at least a cruise flight phase of said flight.     
     
     
       29. The method according to claim 28, further comprising maintaining said flap trailing edge body in said neutral position without flexibly bending during said step a). 
     
     
       30. An airfoil comprising a main airfoil body,   a rigid guide rail connected to and extending rearwardly from said airfoil body,   a carriage arranged to be movable along said guide rail;   a flap including a flap nose member forming a leading edge of said flap and a flap trailing edge body forming a trailing edge of said flap, wherein said flap nose member is pivotably connected to said carriage, said flap nose member and said flap trailing edge body each comprise a supporting structure covered by respective upper and lower cover skins, one of said cover skins continuously extends over and bridges between said flap nose member and said flap trailing edge body so as to connect said flap nose member with said flap trailing edge body, and said flap trailing edge body is elastically flexibly bendable in a plane extending parallel to a chord length of said flap, and   an actuating device that has a selectively variable length and that is pivotally connected to said flap trailing edge body and to said guide rail.   
     
     
       31. The airfoil according to claim 30, wherein said one of said cover skins forms a flexible hinge connection between said flap nose member and said flap trailing edge body, and the other of said cover skins is interrupted by a gap between said flap nose member and said flap trailing edge body. 
     
     
       32. The airfoil according to claim 31, further comprising a support arrangement including a rigid support arm rigidly connected to and extending from said flap nose member and an actuatable supporting device connecting said rigid support arm with said flap trailing edge body between said actuating device and said gap.